Improvement in sewing-machines



'JdHNn LESTER,.-

improvment'in Sewing Machines.

Patented june-13, i871;

lun-115,872;

Ma/"ammi mwmw f' 7 MJ' f Fries.

JOHN H. LESTER, OF BROKLYN, NEWT YORK.

{MPROVEMENT IN SEWlNG=MACHINES.

Specification forming part of Letters Patent No. 115,872, dated .lure 13,1871.

`1 do hereby declare that the following .is a full and exact 4description thereof.

My invention appliesl to that cla-ss of 1na chines in which two threads are employed,

,'orinin g what is known as the lock-stitch, and

relates to the shuttle and means for operating the shuttlewhich introduces the second thread.

My invention is an improvement on that described in the patent issued to G. H. Lenher, dated November 22, 1866.

l will iirst describe what is considered the best means of carrying out my invention, and will afterward designate the points which l believe to be new therein.

The accompanying drawings form a part of this specication.

Figure l is a side elevation of the shaft. Fig. 2 is an end elevation of the shaft. Fig. 3 is a section through all the parts, to wit, shaft and shuttle. Fig. 4 is an end view of all the parts,

to Wit, shaft and shuttle. Eig. 5 is an end view4 ofthe race or lined Work in which the shuttle revolves 5 this figure shows the work as turned down-that is, the notch P, here shown on one side, is really at the top. Fig. 6 is a corresponding plan View of the saine fixe-d part. Fig. 7 is another end view of the shaft alone. Fi g. 8 is another side view of the shaft alone. Fig. 9 is a view of the face of the shuttle alone; and Fig. 10 is a side View ofthe shuttle alone.

Similar letters of reference indicate like parts in all the figures.

The drawings represent the novel parts, with so much of the other parts as is necessary to indicate their relations thereto. The material of all the novel parts may be iron or steel.

A is a portion or' the xed frame-Work of the scwiugfmachine; `B is a circular recess provided' for the shuttle and the operating parts. A deep notch is provided, as indicated by P, at the upper side of the recess B, through which the needle is allowed to descend in producing each stitch. C is the shuttle. 'It carries the thread on a bobbin, F, secured bya screw, G, which screws into apost provided in the shuttle, as represented. I is a spring, which pro- Y duces friction against the under side oi' the bobbin, and thus induces a proper tension on the thread h as it is delivered from the bobbin. The shuttle is provided with a pointed and smooth nose, C', which, at each revolution ot the shuttle, is inserted under the main thread, or between it and the needle; and by distending the loop thus produced the entire shuttle is thrown through the space between the nee die and the thread with an effect which will be readily understood by those familiar with sewin g-inachines. The shuttle is carried around in the cavity D. by the rotation ofthe main shaft of the sewing-machine. The main shaft is rep resented by D. The cavity B is concentric thereto, and the main shaft is extended into this cavity, and peculiarly shaped in order to perform the duties required.

I will designate the several parts of the end of the main shaft by diiierent marks, distinctly explaining, however, that' the Whole may be, and preferably is, a single piece of nieta-l. First, the main shaft is deeply recessed or cut into in the path of the needle, as indicated by the deep recess D1. The material ot' the main shaft is removed very greatly at this point, and in order to provide sufficient strength the shaft isenlarged at this point, as indicated, so that the remaining portion D2 will possess snflicient cross-sectional area. Beyond this contracted neck the main shaft is enlarged within the cavity B, as indicated by D3 l)v1 D5. The snrface between Dl and D4 is hollowed and adapted to lit to a corresponding portion of the shuttle, asindicated in Fig. 2. rlhe point D3 presses fairly against the shuttleand serves as the iinpelling point to drive the shuttle in its con tinnons rotating motion. The point D4 preven ts the shuttle from becoming displaced; and the point or extended and smooth horn D5, in connection with the other parts, performs the function of maintaining the proper condition of the thread as it is successively drawn out and 1ib erated by the passage of the shuttle.

My construction and arran gement possess the very marked advantage over that described in the Lenher patent referred to, that it provides for driving the shuttle eiciently without the introduction ot' the additional parts ofthe mechanisni described in the Lenber patent. In the Lenher construction the shuttle is driven in a horizontal circle, and the upright shaft J with several attachments and connections are introduced for the express purpose of driving the shuttle.. By my improved construction all the parts so introduced are dispensed with, and the main shaft is itself made available to drive the shuttle without requiring any additional part.

In the operation of my invention, the bobbinl F having been filled with thread ofthe proper size, and the screw G having been adjusted so as to induce the proper degree of force in the spring I, and consequently a proper tension on the thread as it is delivered from the shuttle C, the machine is set in operation, and at each descent of the needle, or rather at each commencement ofthe ascent ofthe needle, the nose C ofthe shuttle is insinuated between the slackened thread and the needle, and the loop'thus initiated is enlarged by the progress of the shuttle until it is compelled to pass over, or rather the entire shuttle is thrown through the loop, leaving the thread, which is drawn off. from the bobbin F, as required, in the 'loop thus formed of the mainthread, and as the needle rises and draws up the stitch the proper tension is in duced on both threads and a complete loclr 1. rlhe shaft D recessed at the neck D1, and connected, by a remaining part, D2, withV an enlargement having horns D3, D, and D5, when operated within a race, A, and adapted to serve, relatively, to a shuttle, C C', and to a needle `and its connections, as herein set forth.

2. The combination of the shuttle C C', and the means provided therein for carrying and ydelivering the shuttle-thread, with lthe peculiarly-formed driving means D D1 D2 D3 D4 D5,

operating together in 'a sewing-machine as herein set forth.

JNO, ELLESTER. Witnesses:

W. G. DnY, C. C. LIviNGs. 

